Try forum profile links. I used to get killer backlinks looking for forums that allowed profile links. I had links from mtv.com, cnn.com, etc… real big sites. Fill your profiles full of text about your site and keyword space. Make it seem genuine and not spammy.
Find a person’s photo to upload as your own. Invent a name login & password thats easy to remember and type that wont exist anywhere you go and will validate for length and security strength. (This is how I got my handle years ago… 5 characters was too short for most forums. 6 almost always did the trick with a 7 letter strong password. If 6 was too short on login I’d know to just add another ‘b’ to the end. ) write your bio and stuff in advance. make a gmail account for the identity… youll have to click on a lot of verify links. Obviously don’t use this account for anything since it will be the account most likely to get hacked or phished by bad forums once you registers to a few thousand of them.
ideally its just a few days of searching for forums and cutting and pasting. Make a text file of all the profile page urls… you put them in a publicly shared google doc in link form and then publicly share the doc an fill it full of niche related content. then submit the doc url to google.Google trusts documents…
If you visit a place youve already been to but have forgotten the name will already exist. Just move on…
eventually you can go back and post at these forums legitimately if they allow signature links and post links. you can also use you profile url on the forum as your sig link then comment on popular threads to boost your profile PR. Sometimes you can linkwheel your profile pages too. You can also find a lot of .edu and .gov forums too.
Back in the day it would take about 2 weeks to linkbuild with forum profiles to PR6. PR7 and above required viral tactics and most likely still does.
Create a single blogger blog… syndicate the whole articles… just be sure to post a link to your site in the middle of every post. Then write to posts a day about your keyword space and ping the blog… scrapers sites will steal the full articles and post them on their site.
Don’t spend time worrying about nofollow. An organic site that isn’t trying to artificially influence google will have a healthy mix of mostly nofollow inlinks. nofollow links still provide good value too.